Lighting system

ABSTRACT

A lighting system for a building having rooms ( 35 ) is disclosed which includes a plurality of light collectors ( 12, 14 ) for collecting ambient light, and a plurality of light guides ( 16 ) for conveying the light to a light accumulating vessel ( 20 ). The vessel ( 20 ) has an internal reflective surface ( 21 ). A plurality of second light guides ( 35 ) extend from the vessel ( 20 ) to the rooms ( 35 ) so that light which is collected in the vessel and which reflects in the vessel eventually finds it way to the light guides ( 34 ) supply to the rooms ( 35 ) to illuminate the rooms.

FIELD OF THE INVENTION

This invention relates to a lighting system for lighting rooms of abuilding, dwelling, or the like (collectively referred to as a buildingherein).

BACKGROUND ART

Conventional lighting systems comprise fixed or free-standing lightswhich are located in rooms of a building. The lights are connected to asource of electricity and are turned on and off by a switch which iselectrically connected by wires to the lights and to the source ofelectricity. This form of lighting is of course well known andconventionally used throughout the world.

Conventional lighting systems of this type require the generationelectricity and subsequent infrastructure as well as hard wiring in thebuilding. Whilst the electricity generation facility infrastructure isalso required to supply electricity to buildings for other purposes,there is obviously a saving in energy to be made if at least part of thelighting requirements for a building can be produced without the need ofenergy generation.

Of course, some of the lighting required by a building can be providedby natural light which enters through windows. However, depending on thenature of the building and the location of rooms within the building,usually natural light is not sufficient to sufficient illumination toadequately light the rooms of the building. Furthermore, the obviouslythe use of natural light which merely is provided by way of a windowrequires the windows to be uncovered which, in many environments, is notdesirable.

SUMMARY OF THE INVENTION

The object of the invention is to provide a lighting system which canprovide at least part of the lighting for a building without the need torely on electric power.

The first aspect of the invention provides a light system for abuilding, including:

-   -   at least one light collector for collecting ambient light; and    -   a light guide for conveying light from the collector to a room        of a building.

Thus, by collecting ambient light and conveying the collected light to abuilding by a light guide, at least some of the lighting requirementsfor the building is provided by the collected ambient light, andtherefore the need for electrically powered lights is at least reduced.

In one embodiment of the invention the system further includes lightjunction member, and the light guide comprises a first light guideextending between the collector and the junction member, and a secondlight guide extending from the junction member to the room of thebuilding.

In one embodiment of the invention the light collector comprises a dishreflector for reflecting ambient light towards a focal point, asecondary reflector at the focal point for reflecting light into thefirst light guide.

In one embodiment of the invention a plurality of said light collectorsare provided, each collector being connected to the junction member by arespective first light guide.

In one embodiment of the invention a plurality of said second lightguides extend from the light junction member for conveying light fromthe junction member to the at least one room of the building.

In one embodiment of the invention a plurality of rooms of the buildingare illuminated by the lighting system and a plurality of second lightguides extend from the light junction member to each room of thebuilding.

In one embodiment of the invention the junction means comprises a vesselhaving a highly reflective inner surface so that light which is conveyedinto the vessel by the first light guides reflects within the vesseluntil the light enters one of the seconde waveguides and is conveyed tothe room to illuminate the room.

In one embodiment of the invention the vessel is spherical and linedwith a good reflective material such as halon, reflective paint, etc.

In one embodiment of the invention the vessel includes intensity sensorsfor monitoring the intensity of prescribed wavelengths of light withinthe vessel, and control means responsive to the energy sensor forcontrolling at least one light source for supplying light into thevessel to maintain the light in the vessel as substantially white lightso that white light is supplied to the rooms by the second waveguides.

The invention in a further aspect may be said to reside in a lightingsystem for a building having a plurality of rooms, including:

-   -   a plurality of light collectors for collecting ambient light,        each collector comprising a reflector for reflecting light        towards a point;    -   a light guide having a first end located at the point for        receiving light from the reflect;    -   a light accumulating vessel having a reflective internal        surface, the vessel being connected to each of the light guides        so that light reflected into the light guides is conveyed to the        vessel and propagates within the vessel by reflection from the        internal surface of the vessel; and    -   a plurality of second light guides extending from the vessel to        rooms of the building for conveying light from the vessel to the        rooms of the building to illuminate the rooms.

In one embodiment of the invention the reflector includes a parabolicdish-shaped reflector and the focal point is the focal point of theparabolic reflector at which the end of the first light guide islocated. However, in the preferred embodiment, the collector furtherincludes a concave focusing mirror at the focal point of the parabolicreflector for reflecting the light to a further point at which the firstend of the first light guide is located for conveying the light to thevessel.

In one embodiment of the invention the vessel includes a plurality ofintensity sensors for measuring the intensity of light within the vesselat various wavelengths, control means connected to the intensity sensor,a light source for supplying light into the vessel connected to thecontrol means so that the control means can control the light source toprovide illumination into the vessel for maintaining the light withinthe vessel substantially as white light so that white light is conveyedby the second waveguides to the rooms of the building.

The light source may be a fixed light source connected to the vessel ormay be a light source remote from the vessel and coupled to the vesselby a light guide.

The invention may also be said to reside in a lighting system for abuilding having a plurality of rooms, including:

-   -   a plurality of light collectors for collecting ambient light,        each collector comprising a dish reflector for reflecting light        towards a focal point and a secondary reflector at the focal        point;    -   a light guide associated with each of the collectors for        receiving light reflected by the secondary reflector;    -   a light accumulating vessel having a reflective internal        surface, the vessel being connected to each of the light guides        so that light reflected into the light guides from the secondary        reflectors is conveyed to the vessel and propagates within the        vessel by reflection from the internal surface of the vessel;        and    -   a plurality of second light guides extending from the vessel to        rooms of the building for conveying light from the vessel to the        rooms of the building to illuminate the rooms.

In one embodiment of the invention the vessel includes a plurality ofintensity sensors for measuring the intensity of light within the vesselat various wavelengths, control means connected to the intensity sensor,a light source for supplying light into the vessel connected to thecontrol means so that the control means can control the light source toprovide illumination into the vessel for maintaining the light withinthe vessel substantially as white light so that white light is conveyedby the second waveguides to the rooms of the building.

The light source may be a fixed light source connected to the vessel ormay be a light source remote from the vessel and coupled to the vesselby a light guide.

In one embodiment of the invention the dish reflectors and the secondaryreflectors reflect white light to their respective waveguides so thatwavelengths outside the normal visible spectrum are not supplied to thevessel.

In one embodiment infrared radiation may be reflected to an ancillarylight guide or otherwise collected so that the infrared radiation can beused as a heat source to provide supplemental heating to the building orfor water heating.

BRIEF DESCRIPTION OF THE DRAWINGS

One embodiment of the invention will be described, by way of example,with reference to the accompanying FIG. 1 which shows a preferredembodiment of the invention.

DETAILED DESCRIPTION OF THE EMBODIMENT

With reference to FIG. 1, a lighting system according to one embodimentis shown. The lighting system comprises a plurality of ambient lightcollectors 10 which may be mounted on a roof of a building, or in closeproximity to a building. Each collector 10 comprises a parabolic dishreflector 12 and a concave focusing mirror 14. The mirror 14 is arrangedat the focal point of the parabolic reflector 12 so that ambient lightwhich is reflected by the reflectors 12 is reflected by the mirrors 14to a respective waveguide 16. The waveguide 16 has a first end 17projecting through the dish reflector 12 and located at a point forreceipt of the light reflected by the mirror 14. Other end 18 of thelight guide 16 is connected to a spherical vessel 20 which acts as ajunction vessel for collecting light conveyed by the light guides 16.The vessel 20 has an internal surface 21 which is highly reflective sothat light is simply propagated within the vessel by reflecting aboutthe vessel without any absorption so there is substantially no loss oflight within the vessel 20 and no heating of the vessel 20.

A plurality of second light guides 30 extend from the vessel 20 to rooms35 of a building so that light is conveyed from the vessel to the roomsto illuminate the rooms. In the embodiment shown, each room has twolight guides for supplying illumination, but more light guides could beprovided, depending on the size of the room and the illumination whichis required.

The vessel 30 also has a plurality of sensors 40 for sensing theintensity of electromagnetic radiation in the vessel of variouswavelengths. For example, one of the sensors 40 could sense wavelengthsnear the infrared region of the spectrum, one intensity sensor 40 couldmeasure the intensity of wavelengths in the middle of the visiblespectrum, such as green light, and one of the sensors could measure theintensity of radiation towards the ultraviolet end of the spectrum. Thesensors provide an intensity measure of the various wavelengths whichtherefore provides an indication of the light within the vessel andwhether the light is substantially white light which is required forillumination. Depending on the length of the waveguides 16 and theambient light conditions, the light which is conveyed by the light guide16 to the vessel may be predominantly of a particular wavelength orrange of wavelengths more than others, meaning the light may be slightlycoloured or, alternatively, losses of particular wavelengths within thewaveguide can result in the light being slightly coloured or closer tothe infrared end of the spectrum, rather than evenly distributedthroughout the visible spectrum.

In order to compensate for the loss of any wavelengths, the intensitysensors 40 are connected to a control system 50 which in turn isconnected to one or more white light sources 70. In the embodimentshown, two light sources 70 are coupled to the sphere and are controlledby the control means to provide illumination into the vessel tocompensate for any loss of a particular wavelength so that the lightwithin the vessel is substantially white light, and thereforesubstantially white light is delivered to the rooms for illuminating therooms.

Rather than provide the white light sources 70 on the vessel as shown,the light sources 70 could be coupled to the vessel by a waveguide 71 asillustrated by the light source labelled 70′ in the drawing.

The light source 70 is electrically powered light and therefore someelectrically generated energy is required in order to be supplied to thevessel. However, a significant amount of the illumination is provided bythe collectors 10 and therefore the overall illumination which issupplied to the rooms 35 is predominantly illumination which iscollected by the collectors 10, thereby greatly reducing the reliance onelectricity consumption for supply of illumination. Alternatively, anarray of L.E.Ds could be connected to the vessel 20 to augment the lightcollected by the system. These L.E.Ds could be powered by a photovoltaic array and battery storage.

In order to supply illumination via the collectors 10 and the waveguides16, the ambient conditions require daylight conditions and preferablyclear sky. If there is significant cloud coverage, the amount ofillumination will greatly decrease in the visible range of the spectrum,although infrared radiation probably will remain the same. Thus, thesupply of white light by the sensors 70 is required. Furthermore, atnight time, obviously no light will be collected by the collectors 10and the light sources 70 are required to supply light into the vessel 20which can then be conveyed by the light guides 30 to the rooms 35 ifillumination is required at night.

In embodiment of the invention a single light source 70 is providedwhich is in the form of a fusion light which is comprised of agas-filled envelope in which a bead of sulphur is contained. Theenvelope has a stem which is arranged in a magnetometer so that when themagnetometer is powered, microwave energy causes extremely intenseillumination to be supplied. Such light sources are know, and thereforeneed not be described in any detail hereinafter. However, it isenvisaged that a single light source of this type could supplysufficient illumination to the vessel 20 to provide lighting for areasonably sized building during darkness.

In the preferred embodiment of the invention, each of the light guides30 is provided with a shutter 80 which is arranged on the inside of thevessel 20 and has a contour which matches the curved contour of theinner side of the vessel 20. The shutter is arranged for movementrelative to the end of the light guide 30 in the vessel so that the endof the light guides 30 can be shut off if needed so that illumination isprevented from entering the waveguides so that the lights of the rooms35 can effectively be switched off if needed or desired.

The shutters 80 are preferably controlled by a remote control devicewhich can be located in the room and simply actuated by a user to supplya signal to a detector in the room which in turn conveys a signal to ashutter mechanism for closing the shutters 80 or opening the shutters 80as the case required.

Preferably the light guides 16 and 30 are light guides made according toour assigned International Patent Application PCT/US99/18228(WO00/10044), the contents of which is incorporated into thisspecification by this reference. The light guide disclosed in thisInternational application has the advantage of provided an extremelywide entrance aperture so that light at relatively high numericalapertures is able to enter the waveguides 16 from the mirror 14 and alsoenter the waveguides 30 from reflection within the vessel 20. Thus, whenthe shutters 80 are open and light is propagating within the vessel 20by reflection from internal surface 21, the light will eventually findits way to the end of the light guide 30 and will enter the light guide30 for propagation along the light guide 30 to the rooms 35 in themanner described above.

Since modifications within the spirit and scope of the invention mayreadily be effected by persons skilled within the art, it is to beunderstood that this invention is not limited to the particularembodiment described by way of example hereinabove.

1. A light system for a building, comprising: at least one lightcollector for collecting ambient light; and a light guide for conveyinglight from the collector to a room of a building.
 2. The system of claim1 wherein the system further includes a light junction member, and thelight guide comprises a first light guide extending between thecollector and the junction member, and a second light guide extendingfrom the junction member to the room of the building.
 3. The system ofclaim 1 wherein the light collector comprises a dish reflector forreflecting ambient light towards a focal point, a secondary reflector atthe focal point for reflecting light into the first light guide.
 4. Thesystem of claim 1 wherein a plurality of said light collectors areprovided, each collector being connected to the junction member by arespective first light guide.
 5. The system of claim 2 wherein aplurality of said second light guides extend from the light junctionmember for conveying light from the junction member to the at least oneroom of the building.
 6. The system of claim 2 wherein a plurality ofrooms of the building are illuminated by the lighting system and aplurality of second light guides extend from the light junction memberto each room of the building.
 7. The system of claim 2 wherein thejunction means comprises a vessel having a highly reflective innersurface so that light which is conveyed into the vessel by the firstlight guides reflects within the vessel until the light enters one ofthe seconde waveguides and is conveyed to the room to illuminate theroom.
 8. The system of claim 7 wherein the vessel is spherical and linedwith a good reflective.
 9. The system of claim 7 or 8 wherein the vesselincludes intensity sensors for monitoring the intensity of prescribedwavelengths of light within the vessel, and control means responsive tothe energy sensor for controlling at least one light source forsupplying light into the vessel to maintain the light in the vessel assubstantially white light so that white light is supplied to the roomsby the second waveguides.
 10. A lighting system for a building having aplurality of rooms, including: a plurality of light collectors forcollecting ambient light, each collector comprising a reflector forreflecting light towards a point; a light guide having a first endlocated at the point for receiving light from the reflect; a lightaccumulating vessel having a reflective internal surface, the vesselbeing connected to each of the light guides so that light reflected intothe light guides is conveyed to the vessel and propagates within thevessel by reflection from the internal surface of the vessel; and aplurality of second light guides extending from the vessel to rooms ofthe building for conveying light from the vessel to the rooms of thebuilding to illuminate the rooms.
 11. The system of claim 10 wherein thereflector is a parabolic dish-shaped reflector and the focal point thefocal point of the parabolic reflector at which the end of the firstlight guide is located.
 12. They system of claim 10 wherein thereflector is a parabolic reflector and the collector further includes aconcave focusing mirror at the focal point of the parabolic reflectorfor reflecting the light to a further point at which the first end ofthe first light guide is located for conveying the light to the vessel.13. The system of claim 10 wherein the vessel includes a plurality ofintensity sensors for measuring the intensity of light within the vesselat various wavelengths, control means connected to the intensity sensor,a light source for supplying light into the vessel connected to thecontrol means so that the control means can control the light source toprovide illumination into the vessel for maintaining the light withinthe vessel substantially as white light so that white light is conveyedby the second waveguides to the rooms of the building.
 14. The system ofclaim 10 wherein the light source is a fixed light source connected tothe vessel or a light source remote from the vessel and coupled to thevessel by a light guide.
 15. A lighting system for a building having aplurality of rooms, including: a plurality of light collectors forcollecting ambient light, each collector comprising a dish reflector forreflecting light towards a focal point and a secondary reflector at thefocal point; a light guide associated with each of the collectors forreceiving light reflected by the secondary reflector; a lightaccumulating vessel having a reflective internal surface, the vesselbeing connected to each of the light guides so that light reflected intothe light guides from the secondary reflectors is conveyed to the vesseland propagates within the vessel by reflection from the internal surfaceof the vessel; and a plurality of second light guides extending from thevessel to rooms of the building for conveying light from the vessel tothe rooms of the building to illuminate the rooms.
 16. The system ofclaim 15 wherein the vessel includes a plurality of intensity sensorsfor measuring the intensity of light within the vessel at variouswavelengths, control means connected to the intensity sensor, a lightsource for supplying light into the vessel connected to the controlmeans so that the control means can control the light source to provideillumination into the vessel for maintaining the light within the vesselsubstantially as white light so that white light is conveyed by thesecond waveguides to the rooms of the building.
 17. The system of claim16 wherein the light source is a fixed light source connected to thevessel or a light source remote from the vessel and coupled to thevessel by a light guide.
 18. The system of claim 15 wherein the dishreflectors and the secondary reflectors reflect white light to theirrespective waveguides so that wavelengths outside the normal visiblespectrum are not supplied to the vessel.
 19. The system of claim 16wherein infrared radiation is reflected to an ancillary light guide orotherwise collected so that the infrared radiation can be used as a heatsource to provide supplemental heating to the building or for waterheating.